1. Field of the Invention
The invention described herein relates to the field of military ordnance. In particular it relates to high caliber ammunition fired from weapons in the arsenal of the United States Army, and more specifically to ammunition containers that protect the rounds fired from these weapons. The ammunition containers described herein offer distinct advantages over those that preceded them. The containers provide superior protection from shock, vibration, exposure to the elements and address important concerns related to weight, operational effectiveness, cost, and environmental impact. While specifically developed for mortar ammunition the technology of this invention is readily adapted tank ammunition, grenades, and other ammunition families that utilize the fiber container packaging technology.
2. Background of the Invention
Ordnance used on the modern battlefield and in training exercises by the United States Army must be protected from the effects of vibration, shock and exposure to the elements. Exemplary cases are relatively lightweight, mobile weapons such as the Army""s 60 mm, 81 mm and 120 mm mortars. The inherent portability, flexibility and ubiquity of these weapons dictate that they and the ammunition they fire can and will be exposed to a very wide range of non-ideal conditions.
In particular, these weapons and their ammunition are expected and, indeed, required to perform as designed in conditions that include extreme heat and cold, as well as wet and dusty environs. In addition, ammunition for these mortars is expected to survive high g-loadings such as those that might be experienced when being transported by tracked or wheeled vehicles, carried by soldiers or even delivered by fixed- or rotary-wing aircraft or even by parachute. As such, whose rounds are currently packed in pairs in a metal/fiber packing system.
Recent emphasis on rapid deployment and the requirement for heretofore unimaginable mobility and unprecedented firepower, as exemplified by the US Army""s new Lightweight Brigade Combat Team (BCT), gives all new importance to minimizing the weight and volume associated with packing materials while maintaining the protection required by these highly explosive rounds. In addition, cost and environmental concerns can no longer be ignored and, therefore, must be addressed in an effective manner. These requirements place added restrictions on construction materials and techniques and require that the containers be re-usable and/or recyclable.
The current metal/fiber container packing system for 120 mm mortar ammunition was designed/developed by contractors in the early 1990s. In its current embodiment, the packaging system consists of two PA153 fiber containers inside a PA154 metal container. Two loaded PA153 fiber containers are packaged inside the PA154 metal container to achieve the long term protection to the ammunition against various rough handling environments while still fitting inside the vehicle for operations.
In a typical battlefield or training scenario, the PA153 fiber containers are removed from the PA154 metal container at the point of re-supply. This is a time-consuming exercise, placing an added burden on the soldiers, could leave the mortar cartridges relatively unprotected, and could leave the discarded metal containers subject to loss and/or damage. The final condition is an important consideration when unexpended rounds need to be re-stored.
The existing metal/fiber container system with 2 rounds of ammunition has a gross weight of 101 lb. Because it exceeds the 90-pound maximum lift of a single package by a single soldier, as mandated in Operations Requirement Documentation, it must be handled by two persons.
In order to access the ammunition, the soldiers must first open the metal container, pull out the fiber containers, open the tape-seals of fiber containers and retrieve the ammunition. This is obviously is a very time-consuming process that affects combat readiness. In addition, the tight-fitted fiber containers are difficult to be removed from the metal container under non-ideal conditions such as cold weather where soldiers are wearing heavy gloves.
During military operations, soldiers normally discard the metal containers at the ammunition supply point and only the loaded fiber containers are placed into the storage racks of a mortar carrier. Since it is the metal container that provides most of the environmental protection to the ammunition inside, the ammunition sitting in the racks inside the vehicle can be adversely affected by moisture and rough handling. This can decrease the overall useful life of the ammunition especially if the ammunition is no expended immediately.
Furthermore, metal containers are also often lost or damaged after vehicle uploading and the two container approach to packaging becomes a burden on the soldier should the ammunition need to be repackaged. This is especially important in training situations where ammunition is often re-loaded and returned to an ammunition storage facility for future use. In addition, it may be observed that the fiber containers are not readily recyclable nor re-usable, resulting in higher production costs and environmental impact.
Thus, there is a great and still unsatisfied need for a solution to the problem of producing an efficacious, cost-effective, lightweight container for mortar rounds.
The composite monopack container of the present invention represents a new generation of packing container for mortar ammunition, and addresses the shortcomings of the existing packaging systems. In particular, the container is lightweight, universally adaptable to all existing ammunition types, is capable of fully protecting ammunition without the need of a metal overpack, and is relatively inexpensive to produce, maintain and dispose.
In addition, the container is easy to use and fully back-compatible, that it is compatible with existing ammunition racks, etc., within the inventory. Moreover, the new implementation features mean quicker ammunition re-supply and greater ammunition availability on the battlefield.
The lightweight monopack container is made from lightweight thermoset, flame-retardant composite materials. This composite compound material comprises Vinyl Ester resin and 56% (by weight) fiber glass designed for compression molding of components requiring high structural strength. These elements are subjected to a pressure of 1,500 pounds per square inch (minimum) at 290xc2x0 F. for 5-10 minutes during the molding process. Primary features of the container are formed during the molding process, reducing post-processing time and minimizing production costs.
The monopack container comprises a cap and body assembly sufficiently rugged and impervious to environmental factors to eliminate the need for secondary containment. Unlike its predecessor, the monopack container provides full environmental protection for the ammunition from adverse battlefield conditions at all times until the actual point-of-use and, thus, increases the service life of ammunition and greatly simplified re-packaging operations in cases when ammunition is unpacked but not expended.
Further, it is anticipated that the composite monopack container will provide improved Insensitive Munitions (IM) response compared to the current metal/fiber container packing system. In particular, the composite resin will burn very slowly and evaporate at the elevated temperature (carrying away the heat of evaporation), thus preventing a high pressure built-up inside the container. In addition, the composite container contains minimal amount of metal materials, limited to a small latching system and several tie down rivets, as compared to the current heavy duty PA154 metal container. Therefore, no significant amounts of fragmentations are expected.
Weighing about 7.5 lbs, one embodiment of the monopack container is designed to hold a single cartridge, and be carried or handled by a single soldier. Advantageously, a collapsible type handle is attached to the container exterior surface of the monopack container to facilitate hand-carry of the containerized round for a short distance maneuver. It incorporates alignment features to assure the container cap matches the body assembly in correct orientation for proper closure.
The monopack container has a built-in stacking feature with two exterior octagonal shapes indices located close to each end of the container. The container is closed and sealed by locking the latching system, a mechanism that relies on a heavy duty low profile draw-latch. The seal/latch-system lends itself to operation under extreme environmental conditions, such as intensely cold or foul weather, or NBC (Nuclear, biological, chemical) conditions on the battlefield in which normal gear is augmented by gloves and other special protective equipment that restrict movement and dexterity.
A rubber gasket located inside the cap is compressed onto the top edge of the container body and, hence, provides sealing capability up to a maximum of three pounds-per-square-inch differential pressure while the container is closed and sealed. Thus, the containerized round will remain dry and fully protected while submerged in as much as, for example, 7 feet of water. These sealing features are superior in both ease-of-use and efficacy when compared to the current tape-seal system.
In addition to being waterproof, the container is water-vapor-proof and is able to provide full protection to the ammunition for storage in an uncontrolled outdoor environment for a minimum of one year and in an indoor controlled environment for a minimum of 20 years. The container has exceptional impact strength allowing it to survive under all kinds of battlefield environments and temperatures ranging from approximately xe2x88x9265xc2x0 F. to 160xc2x0 F.
Sub-packing components specially designed to provide a tight package to the interior of the container along with the cartridge assure a quality pack at the loading facilities, to insure optimal protection to the ammunition being transported. These sub-packing components include a fuze support and other cushioning materials that allow the monopack container to be readily adapted to the full array of mortar ammunition, such as for example: high explosive, illuminating, infrared illuminating, and smoke cartridges.
The advantages afforded by the reduced weight, volume, packing material are not limited to the point-of-use. These reductions translate into more munitions in a given volume, more munitions carried and delivered in combat and to obvious general improvements in logistics operation efficiency and reduction in production and shipping costs.
The use of a single layer container packaging system also decreases the burden on soldiers by eliminating the need to remove outer containers prior to uploading to vehicles and decreases the time it takes to re-supply a mortar carrier with ammunition. The quick re-supply of ammunition on the battlefield is literally a matter of life-and-death, and therefore this may be a very significant benefit of the present container system.
The monopack container is designed to be both reusable and recyclable. It, therefore, reduces the environmental burden and decreases disposal costs. The container also significantly saves money during the LAP (loading, assembling and packing) process as the single-layer packaging system simplifies the packing operation and significantly improves the logistics operations by reducing weight and volume and packaging. A security wire seal is used to complete the packing operation makes the unit tamper-proof.
Back-compatibility is yet another feature of the monopack container. The monopack container design is able to work in existing vehicle racks and also can function side-by-side with the existing fiber containers. There will be no need to repackage existing inventory of ammunition.
The composite monopack container represents a new generation of packing container for the 120 mm mortar ammunition. It is readily observable that the monopack container of this invention addresses the needs of the US Army of providing superior protection for mortar round, while reducing production and disposal costs, providing and promoting ease-of-use in the field, and providing substantial weight reduction over their predecessors. While the present invention is described here in connection for 120 mm rounds, the technology is readily extended to rounds used in 60 mm and 81 mm mortars, and also to tank and howitzer ammunition, hand grenades, and other explosive ordnance that requires packaging for safe transportation and currently rely on fiber/metal container packaging technology.